Best ways to seal metal for Paint
Posted: May 25, 2017 By: MattM
A good paint job starts with a good base. This means that you need to make sure you’re sealing up the bare metal and or the work you’ve done at the base. There’s a handful of options we offer, but we decided to break down the best ones for sealing up metal before paint. Read our list below.
- Epoxy Primer- If you want the hands-down best thing to seal any sort of work you’ve done on metal; then epoxy primer is the product you need. Epoxy primer seals metal from the atmosphere and also acts as a barrier between different coatings if you want to layer between products. Epoxy primer can be used on most anything from bare metal to over top of body filler and old paint. If you just finished a repair panel, welding, or even stripping a panel you can seal the metal up with Epoxy Primer immediately to keep it from flash rusting and causing additional rust. With how good epoxy primer works, many have begun applying epoxy primer to seal up a panel and then doing their body filler on top of the cured and abraded epoxy primer. Color is a preference, but we suggest lighter color primers if you’re doing a color that is light or doesn’t have great coverage.
- Self Etching Primer- If you’ve been around the auto body industry for any length of time you’ll know that Self Etching Primer has been the king of bare metal sealants under a paint job. Self Etching primers use an aggressive solvent system that assures a strong bond. Self-Etching Primer is quick drying, and doesn’t require and activator. This means it’s easy to apply and quick to dry, allowing you to move on to the next stage as soon as possible. Self-Etching does require bare, abraded metal as a base. You must be careful applying other coatings on top of it, as some coatings (especially epoxy top coats) won’t adhere correctly to the etching primer. If you stick to the strict rules of using this primer you can be sure that your bare metal panel will be safe from rust and will be a solid base for your beautiful paint job.
- Polyester Surfacer Sealer– A newcomer to the primer world is Poly Sealers. These basically are a sprayable body filler that can be directly to bare metal. They have excellent adhesion and build qualities and allow you to block sand the surface to perfection. Poly Surfacer Sealer is also quite versatile and it can be applied over body filler and pre-existing paint as long as you feather edge those areas to avoid showing through the surface. We like to use a 1-2 punch of epoxy primer over the bare metal followed by Polyester Surfacer Sealer to build up the surface and allow us to block sand to perfection.
Whichever you choose, make sure you prepare the surface correctly and use the products going over top correctly. Once the metal is sealed up with one of the products above you can be sure that you will have a rock solid base to build your paint on top of.